Lint remover for dryer



March 19, 1963 J. F. sTRA'rMAN 3,081,555

LINT REMOVER FOR DRYER Filed Dec. 17, 1959 3 Sheets-Sheet 1 y www @sMarch 19, 1963 J. F. sTRATMAN 3,081,555

LINT REMOVER FOR DRYER Filed Dec. 17, 1959 5 Sheets-Sheet 2 2525.22 zaz"Jrome E Sraman March 19, 1963 J. F. sTRATMAN LINT REMOVER FoR DRYER 3Sheets-Sheet 3 Filed D90. 17, 1959 United States Patent Oiiiice3,081,555 Patented Mar. 19, 1963 3,081,555 LllNT REMUVER FR DRYER JeromeE. Stratman, South Gate, Calif., assigner to Whirlpool Corporation, St.`loseplr, Mich., a corporation of Deiaware Fiied Dec. 17, 1959, Ser. No.860,245 3 Claims. (Cl. 3rd- 79) This invention relates generally to alaundry machine and method, and more particularly relates to a domesticlaundry dryer provided with `an improved apparatus for separating lintfrom the dryer air stream and storing this lint in a receptacle externalof the path of the main air stream so that the dryer can dry successiveloads over a period of time without necessitating the cleaning of afilter after each load or impailing either the drying process or thedryer itself as might otherwise occur when a. iilter is not cleanedafter each load. This lint separation and storage is accomplished byintroducing the exhaust lint-laden air from the dryer into the lintseparator where it is given a swirling action whereby the heavier lintparticles `are separated from the main air stream and introduced alongIwith a very small portion of the total air iiow `into an annulus thathas a tangential outlet leading -to the lint storage means. The majorlint-free portion of the total dryer air flow then flows `axially intoan exhaust outlet after passing `over an air streamliner assembly,

It is an object of the present invention to provide an improved laundrymachine and method.

Another object of the present invention is to provide a dryer apparatuswherein the Ventilating air used in the dryer may be vented from theapparatus after lint and other impurities have been substantiallyremoved there from.

Yet another object of the present invention is to provide a lintseparator and storage unit in a domestic drying machine.

A further object of the present invention is to provide an improveddisposable lint collection means for a domestic dryer.

A still further obiect of the .present invention is to provide a dryerlint separator and storage system wherein the lint is separated from themain air .stream and stored in means external of the main air stream sothat the volume of the main `air stream is not reduced during the dryingof a given load or from load to load thereby assuring that the dryerwill always `operate Lat its designed drying eiiciency.

Many other advantages, features and additional objects of the presentinvention will become manifest to those versed in the art upon makingreference to the detailed description which follows and the accompanyingsheets of drawings in which ya preferred structural embodiment of adryer apparatus incorporating the improved dryer lint separator andstorage unit of the present invention is shown by way or illustrativeexample. It is believed the method contemplated by the present inventionwill be clearly understood from the preferred structural embodimentdisclosed herein and capable of practicing the method.

On the drawings:

FIGURE 1 is a rear perspective View, partially broken away, of adomestic laundry dryer embodying the principles of the presentinvention;

FIGURE 2 is a fragmentary cross-sectional view with parts shown inelevation and with parts broken away illustrating additional details ofconstruction of the lint separator and storage unit provided inaccordance with the principles of the present invention;

FIGURE 3 is an exploded view of the lint separator provided inaccordance with the principles of the present invention;

FIGURE 4 is an end view of the separator cone and batiie; and

FIGURE 5 is an opposite end view of the separator cone and baiile ofFIGURE 4.

As shown on the drawings:

Although the principles of the present invention are of general utility,the preferred structural embodiment herein disclosed by way ofillustrative example constitutes a domestic dryer wherein thermal energyis added to the stream of Ventilating air circulated through the dryertreatment zone by electrical heating means. It will be appreciated thata fuel-fired heating means could be used with equal eiiiciency withoutdeparting from the principles of the present invention.

Thus in the preferred example shown in the drawings, a domestic dryer isindicated generally at 10 and comprises a cabinet having a front wall11, a rear wall 12, side walls 13 and 14, a bottom wall 16, and a topwall 17. Mounted at the rear of the top wall is a control console 18. Toone side of the top wall and forwardly of the console 18, there isprovided an access door 19 opening into a lint collection chamber shownin greater detail in FIGURE 2 and identified generally by the referencenumeral 20.

The interior of the cabinet lltl` is partitioned by a bulkhead 21,thereby forming a front compartment in which is received a rotatabletumbling drum 22 having an apertured rear wall 23 and a rear compartmenthousing various mechanical elements which are utilized in the operationof the dryer.

More specitically, the rear compartment houses an electric motor Z4having a power take-oil? shaft 26 to which is connected a pulley 27driving a belt shown at 21S.

The belt 28 is trained over an idler pulley 29 and the impeller pulley57 which, in turn, rotatably drives the shaft 3G of a centrifugal blowerindicated generally at 31. The idler pulley 29 has a shaft 32 to whichis attached a pulley 33 driving a belt 34 trained over an enlargedpulley 36 carried on a shaft 37 for rotatably tumbling the drum Disposedvertically within the rear compartment formed between bulkhead 21 andcabinet rear wall 12 is a heater box 33. As previously referred to, theillustrative embodiment herein disclosed contemplates the utilization ofelectrical heating elements 39, thereby to temperature-condition dryingair which enters the clothes dryer through a lower portion of themachine front panel, or toe plate, herein identified at 4t) and whichair passes into the heater box 38 through appropriate openings (notshown) in bulkhead 21 and in the lower end of the heater box 38'. Thedrying air then passes upwardly over the dryer heating elements 39 andpasses into dryer drum 22 via an opening 41 formed by a short ductfastened to the upper end of the heater box 38 and passing through thebulkhead 21 in adjacency to the perforate rear wall 23 of the dryer drum22. The rear peripheral edge of drum carries a felt air seal (not shown)which engages the front surface of bulkhead 21 to provide an air sealbetween numbers 21 and 22.

The heated drying air circulates within the dryer drum 22 and picks upmoisture and lint from the clothes tumbling within the dryer drum,leaving the dryer drum 22 through a perforate area in the rear wall ofthe drum 22. The entire perorate rear drum wall 23 communicates throughan opening in bulkhead 21 with inlet 47 of the fan scroll 42 of blower31 which is attached on the rear side of bulkhead 21.

More specifically, the fan scroll 42 shown in FIGURES 2 and 3 comprisesa generally circular body portion 43 having a lfront flange 41E to whichis attached a front plate 46 having a center opening 47 adapted to :beplaced in .stream carrying it, any

s,os1,555

register with a corresponding opening in the rear bulkhead Zl and havinga rear ange 48 apertured as at 49.

Inserted through the aperture 49 of the rear flange@ is a centrifugalimpeller wheel 50 having a circumere'ntial row of impeller blades 51. Asupport and cover plate subassembly indicated generally at 52 carries ajournal box 53 and a bearing support 54, which together serve torotatably support a shaft 3u to which the impeller wheel Sti may beconnected, thereby facilitating rotatable assembly of the centrifugalimpeller 50 within the interior of the fan scroll indicated generally at42. A pulley member shown at 57 can be locked on the end of the shaft 56by set screws S, thereby to cooperate with the pulley belt 2S. Aplurality of fasteners 59' may be passed through corresponding openings60 of support and cover plate sub-assembly 52 and into assembly with anappropriately apertured portion of the rear ilange 4S as at 6l.

The pumping chamber in which the impeller 50 is rotatably driven isessentially circular in configuration and the fan'scroll A4,2 isprovided with aperipheral blower outlet 62 which extends tangentiallyaway from the body portion 43 of the fan scroll 42. The -impeiler 56operates to draw lint-laden air through the centrally located opening-47 of front plate 46 for discharge radially outwardly and tangentiallyinto the blower outlet 62.

As is most clearly shown in FGURE 3, the blower outlet 62 is intangential communication with `a generally cylindrical separator endportion 63 which is an integral part of `fan scroll 42. Fixedly securedto separator end portion 63'is a cap member 66 as is shown in FlGURE 2.

The cap member 66 has an outer peripheral wall 69 formed -with a notchedflange 70 engaging and receiving the edge of the `cylindrical endportion 63 of the fan scroll 42. The cap member also includes aradial-ly inwardly extending'wall 71 that supports the inner wall 67which extends in opposite axial directions from the radial wall 71 todeiine a central axial outlet'opening 68. Walls 67, 69 and 71 cooperateto form an annulus 72 which is spaced radially outwardly of the axialoutlet yopening y68. The annulus 72 is formed with a peripheral bossshown on FGURE 3 at 73, forming a tangential outlet 7 d to which isconnected a lint tube or conduit 76. The conduit 76 extends forwardlyinto the lint collection chamber and is provided with a titting 77 tofacilitate connection thereto of a disposable porous bag filter 7 Shaving -a snapon mouth 79 cooperating with the fitting 77.

Separator end portion y63 and cap member 66 form a chamber 64 in whichthe lint-laden a-ir entering tangentially from blower outlet 62 is`given a swirling spiraling motion axially toward annulus 7 2 and yaxialoutlet opening 68. Since to accomplish the drying process eiiciently itis necessary for blower 31 to move-a relatively large volume of air, theair'will achieve high velocities when passing through the restrictionsoffered by the blower outlet 62 and the chain-ber `64. Since lint `isdenser than air and moves with substantially the same velocity as theair lint suspended in the air stream will be subjected to `greatercentrifugal forces within chamber 64 than the air stream. Due to theselarger centrifugal forces, the lint will have a tendency to iforrn alayer directly adjacent the inner periphery `of end portion 63 andwall'69 of cap member 66. Of course lthe lint in moving to this outerlayer displaces the air inwardly such that by the time the air streamhas spira-lly progressed to the vicinity of the annulus 72 and to thebeginning of axial outlet opening '68 substantially all of the lintincluded in the air stream in chamber `6ft will be in the outerperipheral layer of the air stream and thus be forced into annulus 72 bythe axially progressing spiraling motion of the air stream. iIn practicethe radial thickness of the lint `area will always be less than theradial thickness of the annulus 72 so therefore some air will. alsoenter the annulus 72 with the lint. Wall 7l of annulus 72 serves to stopthe axially spiraling progression of the lint layer l and that part ofthe air stream included between walls 67 and `69 of annulus 72 andcauses both to move in circular lmotion within the annulus 72 where boththe lint and air pass through tangential` outlet 74, through lintconduit 76 and into the disposable porous bag -lter 78 where the lint istrapped and the air passes through the porous walls.

To accommodate venting of the major portion of the air stream with theline separated out, the inner wall 67 may be connected by a hangedfitting S6 fastened to the rear wall l2 to `a ydischarge opening 81bounded by an outwardly extending flange 82 yfor facilitatingconnectionthereto of a Vent pipe, if desired. Thus, the machine is vented to theatmosphere through the back of the cabinet. lt will be understood themachine could also vent to a condenser for recirculation flow back intothe dryer.

The discussion ofthe invention to this point has been concerned withthat small portion of the total air flow and the lint layer that enteredannulus 72, but as can be seen in FlGURE 2, and neglecting the presenceof ele'- ment 3 within chamber 64, the major portion of the lint freeair stream will continue in a spiraling, axially progrossing ilowpattern along wall 67 and pass through outlet openings 68 and 81 intothe atmosphere. This llow pattern for the major portion of the air flowordinarily would be satisfactory if the dryer did not contain anysubstantial external duct work, but in the majority of installations itis usually most desirable to vent the dryer to the outside atmospherewith external venting If the major portion of the air flow were allowedto continue to spiral through the external duct work system, it would ineffect cause a large increase in the friction surface that the air wouldpass over in traversing the vent system and thus cause an undesirabledecrease in air low with resultant ineiiciencies to the drying process.

In order to avoid a drop in dryer eiiiciency which conceivably might becaused by the spiralling or swirling motion imparted to the exhaustingair stream, there is further provided, in accordance with the principlesof the present invention, a separator baille and cone designed andlocatedl to streamline the flow of the exhaust air. ln this regard,reference is particularly made to FIGURES 3, 4 and 5 wherein is shown aseparator baille and cone indicated generally at 83` and comprising acylindrical body portionL 84 considerably smaller in diameter than thecylindrical swirl chamber 64 and llanged as at S6 to receive fasteners87 retaining the separator baffle and cone in rm assembly with thebulkhead 2l. The cylindrical body portion S4 terminates in a cone 88,the apex of which is in alignment with the end of the swirl chamber 64.

A plurality of radially outwardly extending bafiles or iins are providedon the separator baffles and cone 83 including, in this particularembodiment, a pair of diametrically opposed baffles 89 and a pair ofdiametrically opposed axially shorter bal-lies 96. Each of the baffles89 has a portion 91 extending radially outwardly of the cylindrical bodyportion 84 and terminating in a curved portion 92, both curved portionsextending in the same direction and disposed to present the smoothcurved portion towards the incoming air stream to reduce turbulence.

The two ballles 90, 9l, extend radially outwardly from the conicalportion 88 and project axially therebeyond into the axial outlet 63inwardly of the inner wall 67. The axially innermost portion of eachbaille has a portion 93 which projects radially outwardly beyond theinnermost edge of the inner wall 67.

Each of the bailles 89 also extends beyond the cylindrical body portionS4 and the cone portion `88 to the end limit prescribed by the batiies90, Gti, however, the curved portions 92 terminate opposite the coneportion 88, thereby providing four circumferentially spaced Vaneportions in the outlet 68.

The separator baille and cone 83 operates to streamline the tlow ofexhaust air vented through the axial outlet 68, thereby preventing adrop in dryer efiiciency.

Present lint ygathering systems provide for a screen or bag placed tointercept the entire air flow system and are located in what sometimesis an inconvenient location lsuch that regardless of the location, thelint screen or bag has to be cleaned out after every load or the dryerwill not dry effectively. It is common knowledge that dryer operatorsgrossly neglect this cleaning out of the lint screen or bag to theextent that the machine will no longer function as a dryer plus thecondition where lint builds up upstream of the filter to such an extentthat it actually cannot be removed when the Afilter is eventuallycleaned and thus becomes a tire hazard. It is seen that this inventionprovides for a method of lint separation and storage that effectivelyseparates the lint (actual tests indicated that at least 95% of the lintis separated from the main air. stream) from the air stream and storesthis separated lint in a porous receptacle external to the major airflow path. With this lint system countless loads can be dried over along period of time with no maintenance of the system and without a lintbuild up in the main air stream with the resultant reduction in air ilowand the accompanying drying inef'liciencies.

Although minor modifications might be suggested by those versed in theart, it should be understood that I wish to embody within the scope ofthe patent warranted hereon, all such modifications as reasonably andproperly come within the scope of my contribution to the art,

The embodiments of the invention in which an exclusive property orprivilege is claimed are delined as follows:

l. A laundry dryer comprising -a cabinet having front, rear, side andtop Walls, tumbling drum means in said cabinet, a bulkhead in saidcabinet partitioning said cabinet into a front compartment for the drummeans and a rear compartment, -a heater tbox in said rear compartmenthaving a lower inlet and yhaving an outlet extending through saidbulkhead, through which air is drawn and supplied intro said -frontcompartiment at elevated temperatures to pick up moisture land lint fromthe clothes tumbling in the drum means, a fan scroll mounted in saidrear compartment including an inlet in said bulkhead, a center inletcentrifugal impeller in said scroll drawing lint-laden air from 4thefront compartment into said scroll through said inlet in said bulkhead,said scroll having -an annular diffuser portion extending generallytangentially upwardly from said impeller, a generally cylindrical lintseparator connected to and disposed tangentially with respect to saidannular diffuser portion, said lint separator having an axial outletformed therein cxtending to the rear wall of said cabinet, through whichsubstantially lint-free air is discharged, and said lint separatorhaving a tangential outlet formed therein and a radial wall adjacentthereto whereby lint-laden air is discharged through said tangentialoutlet, a lint collection chamber in said cabinet, sa-id top wall havingan access door therein in register with said lint collection chamber,sand a porous bag filter inserted through said access door into saidlint collection chamber and connected to said tangential outlet, therebyto collect the lint for disposal.

2. A laundry dryer as defined in claim 1, and a separate cone and baillemeans in said lint separator to streamline the How of air vented throughsaid axial outlet.

3. In la blower having `an impeller and a diffuser,

means forming a generally cylindrical swirl chamber having an inletdisposed tangentially with respect to said dituser and receivinglint-laden air with a swirling motion lof the air stream,

a cap member on one end of `said swirl chamber comprising an innercylindrical wall forming an axial air outlet and 'forming together withsaid cylindrical swirl chamber a circumferentially continuous annulusspaced concentrically outwardly of said axial air outlet adjacent oneend of said swirl chamber,

said cap having a tangential outlet formed in said annulus to dischargelint-laden air from said annulus therethrough,

and a separator member in said swirl chamber comprising a cone por-tionextending through said swirl chamber and forming together with the outerwalls of the chamber an annular space and a plurality ofcircumferentially spaced vanetype bafiies on said cone portion extendingradially outwardly and projecting axially beyond the end of said coneportion into said axial outlet,

`said separator member operable to streamline the ow of vair throughsaid axial outlet.

References Cited in the tile of this patent UNITED STATES PATENTS1,686,719 Wood Oct. 9, 1928 2,010,128 Arnold Aug. 6, 1935 2,240,291Engles Apr. 29, 1941 2,813,353 McMillan Nov. 19, 1957 2,941,308 Cobb etal. June 21, 1960 FOREIGN PATENTS 278,928 Great Britain Oct. 20, 1927

3. IN A BLOWER HAVING AN IMPELLER AND A DIFFUSER, MEANS FORMING AGENERALLY CYLINDRICAL SWIRL CHAMBER HAVING AN INLET DISPOSEDTANGENTIALLY WITH RESPECT TO SAID DIFFUSER AND RECEIVING LINT-LADEN AIRWITH A SWIRLING MOTION OF THE AIR STREAM, A CAP MEMBER ON ONE END OFSAID SWIRL CHAMBER COMPRISING AN INNER CYLINDRICAL WALL FORMING AN AXIALAIR OUTLET AND FORMING TOGETHER WITH SAID CYLINDRICAL SWIRL CHAMBER ACIRCUMFERENTIALLY CONTINUOUS ANNULUS SPACED CONCENTRICALLY OUTWARDLY OFSAID AXIAL AIR OUTLET ADJACENT ONE END OF SAID SWIRL CHAMBER, SAID CAPHAVING A TANGENTIAL OUTLET FORMED IN SAID ANNULUS TO DISCHARGELINT-LADEN AIR FROM SAID ANNULUS THERETHROUGH, AND A SEPARATOR MEMBER INSAID SWIRL CHAMBER COMPRISING A CONE PORTION EXTENDING THROUGH SAIDSWIRL CHAMBER AND FORMING TOGETHER WITH THE OUTER WALLS OF THE CHAMBERAN ANNULAR SPACE AND A PLURALITY OF CIRCUMFERENTIALLY SPACED VANETYPEBAFFLES ON SAID CONE PORTION EXTENDING RADIALLY OUTWARDLY AND PROJECTINGAXIALLY BEYOND THE END OF SAID CONE PORTION INTO SAID AXIAL OUTLET, SAIDSEPARATOR MEMBER OPERABLE TO STREAMLINE THE FLOW OF AIR THROUGH SAIDAXIAL OUTLET.